This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A103419 #14 Jul 26 2015 14:03:08
%S A103419 1,1,4,6,14,28,59,117,239,484,980,1973,3973,7989,16054,32227,64653,
%T A103419 129628,259787,520440,1042305,2086938,4177680,8361557,16733221,
%U A103419 33482909,66992641,134028938,268128902,536373288,1072934271,2146173471,4292842170,8586488355
%N A103419 Number of compositions of n in which the least part is odd.
%H A103419 Alois P. Heinz, <a href="/A103419/b103419.txt">Table of n, a(n) for n = 1..1000</a>
%F A103419 G.f.: Sum((1-x)^2*x^(2*n-1)/((1-x-x^(2*n))*(1-x-x^(2*n-1))), n=1..infinity).
%F A103419 G.f.: Sum(x^k/((1-x)^k*(1+x^k)),k=1..infinity). - _Vladeta Jovovic_, Mar 02 2008
%F A103419 a(n) ~ 2^(n-1). - _Vaclav Kotesovec_, May 01 2014
%p A103419 b:= proc(n, i) option remember; `if`(n=0, irem(i, 2), add(
%p A103419 (t-> b(t, min(i, j, `if`(t>0, t, j))))(n-j), j=1..n))
%p A103419 end:
%p A103419 a:= n-> b(n$2):
%p A103419 seq(a(n), n=0..40); # _Alois P. Heinz_, Jul 26 2015
%t A103419 Rest[ CoefficientList[ Series[ Expand[ Sum[(1 - x)^2*x^(2n - 1)/((1 - x - x^(2n))*(1 - x - x^(2n - 1))), {n, 35}]], {x, 0, 35}], x]] (* _Robert G. Wilson v_, Feb 05 2005 *)
%Y A103419 Cf. A103420-A103422, A027187, A027193, A026804, A026805.
%K A103419 easy,nonn
%O A103419 1,3
%A A103419 _Vladeta Jovovic_, Feb 04 2005
%E A103419 More terms from _Robert G. Wilson v_, Feb 05 2005